Loading coils find wide-spread use in the telephone industry wherein the coils are connected in series with individual telephone wires to balance detrimental effects of capacitance between wire pairs and, thus, improve signal transmission characteristics. The failure to balance the capacitance effect results in attenuation and distortion of telephone conversations. Traditionally, arrays of loading coils have been packaged in steel or other metallic casings. In copending application Ser. No. 864,304, filed Dec. 27, 1977, now U.S. Pat. No. 4,172,965, in the names of J. D. Eyestone and M. E. Szymanski, there is shown a packaged loading coil assembly that is encased in a plastic housing. Plastic housings of this type are made up of a number of component sections which must be bonded together and bonded to a stub cable containing wire pairs that are connected to the telephone communication wires.
The present invention is particularly concerned with facilities for bonding a plastic component of a loading coil housing to the plastic sheath that jackets a stub cable that also has a coiled section. It is known that plastic parts of various types of housings may be bonded together by extruding a bonding plastic bead along a juncture of the parts. In other situations, thermoplastic parts of a container have been joined by heating and applying pressure to a juncture between the parts. In U.S. Pat. No. 2,319,683 there is shown an apparatus for joining two sections of a bottle-like thermoplastic container. More particularly, the patent discloses apparatus for rotating the parts of the container while applying heat and pressure to a juncture between the parts so as to soften and fuse a bead on one part to the other part.